import java.util.Scanner;

public class Main1630 {
    public static void main(String[] args) {
        Scanner sc =new Scanner(System.in);
        int n= sc.nextInt();
        if (n>=10){
            System.out.println(n*1.2);
        }else {
            System.out.println(n*1.5);
        }
    }
}
